Pneumatic hammer



(No Model.)

E. N. TRUMP.

PNEUMATIG HAMMER.

No. 348,870. Patented Sept. 7, 1886.

WITNESSES @www Attorney of the piston.

UNITED STATES PATENT Carica.

EDWARD N. TRJIMP, OF SYRACUSE, NET YORK.

PNEUMATIC HAMMER.

SSPECIFICATION forming part of Letters-Patent No. 348,870, dated September 7, 1886.

Application filed December l0, 1885. Serial No. 185,213. (No model.)

To all whom, it may concern:

Be it known that I, EDWARD N. 'IRUMP, a citizen of the United States, residing at Syracuse, in the county of Onondaga and State of New York, have invented certain new and useful Improvements in Pneumatic Hammers; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings.

The object of my invention is to provide an improved form ot' percussion-tool or pneumatic hammer, in which the combined piston and hammer strikes upon the anvil-head of a tool-holder either within or outside of the cylinder, the tool-holder transmitting the blow to the bit or tool connectedtherewith, and being retracted to position for receiving other blows by spring coiled around the holder under the anvil-head by hand pressure against the bit used, or by other suitable means. The implement thus formed being adapted to the cutting of stone and metals, carving wood, and other materials, and for riveting, chipping, and calking iron, steel, &c., combines in simple form and in one tool the means for effectively performing a wide range of work. Compressed air or other elastic medium can be used as motive force.

In the drawings, Figures l and 2 represent longitudinal sections of different forms of my device.

Like letters indicate corresponding parts.

Two communicating chambers ol' unequal diameters form the cylinder A. Hammerpiston B is fitted to the cylinder, which is provided with inlet G, transmission-port H, and exhaust-port I. The piston opening and closing the transmission and exhaust ports, no valves are required. An air-port, K, is provided, through which air is admitted and discharged from space back of enlargement of piston. rIhis port is placed slightly below the end of enlarged cylinder, so as to confine alittle air to cushion the reverse movement The lower end of the cylinder is closed by a head, F, perforated through its center.

In Fie. l the piston is provided with an elongated hammer end e, which passes through this head and strikes the anvil-head C of toolholder C L, carried in external ease, R.

In Fig. 2 the tool-holder C L is carried in the cylinder-head, the anvil C receiving the blows of the hammer-piston within the main cylinder-chamber.

The tool-holder C L is provided with chuck or other suitable device for holding bits to be used, and a spring, P, is coiled around the stem below the anvil-head C, to return it to position for receiving other blows of the piston after it has been drivemforward, or the spring may be dispensed with and the anvil returned by pressure on the tool.

A keyway is cut longitudinally` through the tool-holder and casing, as shown in cross-section in Fig. l, and a narrow key, M, inserted to vkeep the tool from turning'. A screwcollar, N', engaging with collar() on the shank of the tool-holder, serves to regulate the force of the blow by drawing the anvil C more or less away from the hammer.

rlhe action ofthe device is as follows: Compressed air being admitted through inlet G, thepiston B is driven down and delivers its blow. After the piston has passed inductionport H, the compressed air passes through and enters the larger part of the cylinder, when, by reason of the greater area of that end of the piston, the piston is forced back.

until it uncovers the exhaust-port I, when the air escapes and a repetition ot' the action occurs. On the direct forward movement of the piston the smaller end receives the full pressure of the motive force. On the reverse movement the motive force works expansive] y.

In a pneumatic hammer, two communicatroo 1o adapted to receive blows from said hammer,

and traversing a ease formed in head of larger chamber or attached thereto, substantially as shown and described.'

In testimony whereof I affix my signature in presence of two Witnesses.

e EDWARD N. TRUMP.

Vitnesses:

A. R. GILLIS, FRANK STRAHL. 

